Analog to Digital Converters (ADCs) are employed in many technological areas. For example, an ADC may be employed to convert sound entering a microphone into a digital signal that can be stored and processed by a digital computing system. The ADC then converts the sample into a corresponding digital value. Certain ADCs employ capacitors to sample an analog signal. A Successive Approximation Register (SAR) is one type of ADC, which may be formed by integrated circuits. As integrated circuits shrink, however, SAR circuits may exhibit electrical current loss in the form of increased relative channel leakage due to the low threshold voltage of particular sampling switches coupled to the capacitor array of the SAR. Channel leakage is nonlinear compared to signal levels, and therefore this introduces noise distortion to a SAR ADC, which is to be avoided. Other current losses occur when the capacitors of the SAR capacitor network leak current through a comparator, or through other SAR circuit components.
Embodiments of the disclosure address these and other limitations.